TABLE XLII. 



Systematic Survey of those Primitive Organs which must probably be 

 regarded as homologous in Worms, Articulated Animals, Soft-bodied 

 Animals, and Vertebrates. 1 " 



I. Products of the Differentiation of the Skin-sensory Layer. 



II. Products of the Differentiation of the Skin-fibrous Layer. 



III. Products of the Differentiation of the Intestinal-fibrous Layer. 



IV. Products of the Differentiation of tlie Intestinal-glandular Layer. 



